Terminal clamp



July 27, 1937. w. e. MYLIUS 2,088,481

v TERLMINAL CLAMP Filed May 21, 1936 WITNESSES: INVENTOR Patented July 27, 1937 UNITED STATES 2,088,481 TERMINAL CLAMP Walter G. Mylius,'Summit, N. L, assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa", a corporation of Pennsylvania Application May 21, 1936, Serial No. 80,968

1 Claim. (Cl. 173-259) The present invention relates to terminal clamps for electrical conductors.

Although the clamp hereinafter described was developed primarily for the electrical conductors 5 associated with watthour meter installations, and particularly when a plurality of such meters are mounted on a channel or other type of enclosures, it obviously is not limited thereto and is applicable to any installation where it is desired to firmly and positively grip a conductor or other device.

It is recognized that the clamp art is a crowded one. However, all of the clamps which are now available are subject to the defect that they involve a substantial number of parts, they are not strong enough to ensure a positive clamping action, or are not strong enough to permit exerting a sufficient clamping force without danger of breaking or spreading the parts of the clamp. I It is an object of the present invention to provide. a strong and eflicient clamp construction which is relatively simple to manufacture and may readily be used to effect a strong mechanical and good electrical clamping action. The invention will best be understood from the following description and the accompanying drawing, in which:

Figure 1 is a plan view of a clamp constructed in accordance. with the present invention;

Fig. 2 is a view in vertical section taken on the line II -II of Fig. 1,

Fig. 3 is a view in perspective of an element of the clamp shown in the preceding figures, and

Fig. .4 is a. view in side elevation of the clamp shown in Figs. 1 and 2.

Referring'more particularly to the drawing, the clamp comprises a member 2 substantially of U- shape havingparallel legs 4 and 6. The dimensions of the member 2, of course, are chosen to 40 meet the particular requirements of 'a given installation but the distance between the legs 4 and 6 should be such that a conductor of substantial size may be received between them.

The member 2 may be mounted on a support in any desired manner as by a supporting strap 8 to which the clamp is secured as by a screw I0 extending through the base of the member 2. The supporting strap 8 may also serve the purpose of effecting an electrical connection to the clamp.

Referring to Fig. 3, it will be noted that the innerconfronting faces of the legs 4 and 6 are provided with segmental screw threads I2. These threads are cut from an axis extending centrally between the legs and preferably are of a shape as illustrated more clea y. in 2, n

which the upper surface of each thread is substantially horizontal, or at least it approaches the horizontal more closely than the lower portion of the thread.

The clamping action is effected by a member I4 which extends between the legs 4 and 6 and is preferably integral with a collar I6 of rectangular form whichembraces the outside of the legs, as shown more clearly in Fig. 1.

A screw I8 of a diameter to engage the threads I2 is rotatably mounted in the base of the member I I. This may be accomplished, as illustrated in Fig.2, by providing a reduced lower portion on the screw which may be extended through an aperture in the base of the member and upset, as shown, to prevent removal thereof.

It should be apparent that when a conductor or other object is inserted between the legs of the U-shaped memberi, the member I4 may be forced downwardly against it merely by rotating the screw I8 with a. screw driver. In this action, the clamp portion I4 is moved into positive contact with the conductor or other member and substantial pressure may be applied. Ordinarily, such pressure would tend to spread the legs of the U-shaped member 2 and break the threaded engagement with the screw'l8. However, as the collar It moves downwardly with the clamping member, it is always at a position to counteract the tendency of the legs 4 and 6 to spread. Inasmuch as the width of the collar I6 is substantially the same as the distance between the outer faces of the legs, such spreading cannot occur and it has been found in practice that a force substantially greater than could heretofore be applied may safely be applied to the screw I8 without breaking the parts of the clamp, or permitting a d.isc0nnecti0n between the threads in the legs and screw I8.

Preferably the collar I6 and the screw I8 are removed'from the member 2 before the conductor is placed between the legs 4 and 6. This greatly facilitates the installation of the wiring and avoids the usual necessity of threading the conductor through the clamp.

The clamping member being substantially of cup shape, it has been found convenient in practice to form it of brass or similar material by a simple stamping operation. Also the member 2 with its threads may also be stamped from similar material. It alsohas the advantage of being able to remove the cup and lay the wire or cable into the stirrup, then replace the cup and clamp tight. Thisis. quite an advantage when wires are run continuously through meters to load or several meters in channel installations. This results in a uniform product and materially decreases the cost of the assembly. y

In accordance with the invention, therefore, an

unusually strong and rigid clamp has been obtained which is capable of exerting a greaterclamping force and with afewer number of parts than clamps heretofore used. It is readily conceivable that many modifications may be made and the exact construction-shown by the invention should not be limited, except by the scope of the appended claims.

I claim as my invention:

In a terminal clamp, a member of U-shape comprised of fiat strip material, an aperture through the base of the U to facilitate attachthe.length of said screw.

said U-shapedmember, means for rotatably securing the end of said screw to the cup base between said slots, the sides of said cup being proportioned to constitute a. continuous collar engaging the outer faces of the legs of the U-shaped member and of a depth substantially the same as Wi L'rER G. MYLIUS. 

